The British government has ordered a review into the country's air traffic control system on Tuesday after a glitch stranded thousands of passengers and caused delays that are set to last for days
More than 1,500 flights were cancelled on Monday, which was a public holiday and one of the year's busiest travel dates as school holidays draw to a close.
Transport Secretary Mark Harper said the incident was the worst of its kind for nearly a decade and ordered an independent review.
This was a technical fault, he told GB News. We do not think this was a cyber-security incident.
Although the system was brought back online within hours, the United Kingdom's National Air Traffic Services said the backlog of flights would last for several days.
That's because airline schedules have been disrupted, and many flight crews are still out of place.
I know people will be enormously frustrated by the disruption that's impacting them, Prime Minister Rishi Sunak said in a broadcast statement.
Thankfully things like this are rare and the issue itself was fixed in a matter of hours, but the disruption obviously is continuing and will last for a little while longer.
British Airways was the worst-affected airline. It said it was working to get back on track and offered short-haul passengers the option to change their flight dates for free.
Meanwhile, budget carrier Ryanair said on Tuesday that it expected considerable flight delays plus some further flight cancellations.